convert ASCII TABs to ASCII SPACEs

Converted all ASCII tabs to ASCII spaces using a 8 character
tab stop, for all files, except for all Makefiles (plus rpm.mk).
The `git diff -w` reports no changes.

HOWTO.INSTALL

@@ -10,7 +10,7 @@ Open up the 'Assets' tag below a given release and download these RPMs:
 
     * calc*.rpm
 
-	- all that is needed if you just want to use calc
+        - all that is needed if you just want to use calc
 
 If your platform supports rpm and matches one of the "calc*.rpm" files, you
 may just install that "calc*.rpm".  For exammple on an x86_64 system:
@@ -25,7 +25,7 @@ files for use in other programs:
 
     * calc-devel-*.rpm
 
-	- calc *.h header and *.a lib files for use in other programs
+        - calc *.h header and *.a lib files for use in other programs
 
 Alternately to the above github link, you might try looking at the RPMs under:
 
@@ -209,10 +209,10 @@ the standard Microsoft Windows developor environment to compile calc.
 
 You should determine if these Makefile variables are reasonable:
 
-    INCDIR		Where the system include (.h) files are kept.
-    BINDIR		Where to install calc binary files.
-    LIBDIR		Where to install calc link library (*.a) files.
-    CALC_SHAREDIR	Where to install calc help, .cal, startup, and config files.
+    INCDIR              Where the system include (.h) files are kept.
+    BINDIR              Where to install calc binary files.
+    LIBDIR              Where to install calc link library (*.a) files.
+    CALC_SHAREDIR       Where to install calc help, .cal, startup, and config files.
 
 You may want to change the default installation locations for
 these values, which are based on the 4 values listed above:
@@ -227,25 +227,25 @@ these values, which are based on the 4 values listed above:
 If you want to install calc files under a top level directory, then set the T value:
 
     The calc install is performed under ${T}, the calc build is
-    performed under /.	The purpose for ${T} is to allow someone
+    performed under /.  The purpose for ${T} is to allow someone
     to install calc somewhere other than into the system area.
 
     For example, if:
 
-	BINDIR= /usr/bin
-	LIBDIR= /usr/lib
-	CALC_SHAREDIR= /usr/share/calc
+        BINDIR= /usr/bin
+        LIBDIR= /usr/lib
+        CALC_SHAREDIR= /usr/share/calc
 
     and if:
 
-	T= /var/tmp/testing
+        T= /var/tmp/testing
 
     Then the installation locations will be:
 
-	calc binary files:	/var/tmp/testing/usr/bin
-	calc link library:	/var/tmp/testing/usr/lib
-	calc help, .cal ...:	/var/tmp/testing/usr/share/calc
-	... etc ...		/var/tmp/testing/...
+        calc binary files:      /var/tmp/testing/usr/bin
+        calc link library:      /var/tmp/testing/usr/lib
+        calc help, .cal ...:    /var/tmp/testing/usr/share/calc
+        ... etc ...             /var/tmp/testing/...
 
     If ${T} is empty, calc is installed under /, which is the same
     top of tree for which it was built.  If ${T} is non-empty, then
@@ -341,7 +341,7 @@ before you install:
 Calc is distributed with an extensive collection of help files that
 are accessible from the command line.  The following assume that you
 are running calc from the distribution directory or that you have
-installed calc.	 In these examples, the "; " is the calc prompt, not
+installed calc.  In these examples, the "; " is the calc prompt, not
 something that you type.
 
 For list of help topics:
@@ -392,7 +392,7 @@ a numner of important make rules and thus fail to properly compile calc.
 ##
 ## Calc is distributed in the hope that it will be useful, but WITHOUT
 ## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
-## or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU Lesser General
+## or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
 ## Public License for more details.
 ##
 ## A copy of version 2.1 of the GNU Lesser General Public License is
@@ -400,8 +400,8 @@ a numner of important make rules and thus fail to properly compile calc.
 ## received a copy with calc; if not, write to Free Software Foundation, Inc.
 ## 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 ##
-## Under source code control:	1999/09/27 20:48:44
-## File existed as early as:	1999
+## Under source code control:   1999/09/27 20:48:44
+## File existed as early as:    1999
 ##
-## chongo <was here> /\oo/\	http://www.isthe.com/chongo/
-## Share and enjoy!  :-)	http://www.isthe.com/chongo/tech/comp/calc/
+## chongo <was here> /\oo/\     http://www.isthe.com/chongo/
+## Share and enjoy!  :-)        http://www.isthe.com/chongo/tech/comp/calc/